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  Topic Review (Newest First)
12-10-2011 06:40 AM
bobperry tdw:
Knee is much better thanks.
12-10-2011 12:14 AM
Geoff54 Nice looking Yacht and really interesting to read the story behind it.

I hope I’m not asking too much - I have a simple question which may be require too long or complicated an answer for here - I won’t be offended if you tell me to go and read up on design principles (would you mind pointing me in the right direction?). Also, I believe that “Limit of Positive Stability” is exactly the same as “Angle of Vanishing Stability” i.e. the zero axis when the Center of Gravity is directly above the Center of Buoyancy, before which (in the absence of any other forces), a boat will right and beyond which it will continue to invert. If I’m wrong, that might explain things, otherwise…

I was surprised to read that that achieving a Limit of Positive Stability of 135 degrees “can be a challenge for some cruising boats”. I always assumed that, within some reasonable limit, achieving a higher AVS was mostly a matter of lowering the C of G by using a deeper and/or heavier keel. I took a quick look at the R.Y.A. Stability List and while there are many boats with numbers under 135, there are quite a few respected cruising yachts with numbers significantly above that (examples include Nordship 40DS – 140, Island Packet 485 – 143, Swan 602 – 153, Sweden Yachts 42 – 156, Vancouver 34 – 166). There are even a few with an AVS of 180, which I didn’t realize was possible – a cork ball with a six inch nail stuck in it, maybe.

I always thought that lower AVS was a compromise because of some combination of cost, desire to keep the overall displacement down or sacrificed because of form stability (cue – wide butt discussion).

I assume I’m missing something but I’m not quite sure what.


12-09-2011 10:59 PM
Originally Posted by bobperry View Post
Yes, LOCAL HERO is the only movie I own and I own two copies, just in case. ( In my best Mac voice) I also have the soundtrack on LP and CD.

The dialogue is so profound.
"And are there two G's in bugger off?"
Damn ... I only have the one DVD but I do have it on VHS .... but my player died ... I can claim one up you on the audio ... Vinyl, CD and on my hard drive.

ps - How's the knee ?
12-09-2011 10:39 PM
bobperry tdw:
Yes, LOCAL HERO is the only movie I own and I own two copies, just in case. ( In my best Mac voice) I also have the soundtrack on LP and CD.

The dialogue is so profound.
"And are there two G's in bugger off?"
12-09-2011 10:17 PM
tdw Nice one Maestro. She is truly a lovely boat. Then again I've noticed you have some empathy with yacht design. Maybe you should consider it as a career.

Hey Caleb, I have it on good authority that BP also has half way reasonable taste in movies .... one of which combines splendid movie making with Mark Knopfler.

hint ... "I used to get headaches when I drove a Chevvy".

Bob ... I cannot for the life me figure out why anyone would want to put a hard dodger onto a deck saloon. Beggars belief.
12-09-2011 02:19 PM
bobperry Hello:
Daryl is on his way over here right now. I''ll suggest that for the next boat.

My job as the designer is to let the client think he can have anything he wants. Then I slowly bring the client back to reality while trying to preserve the vision. I do not use the word "compromise" it's too defeatist for me.
12-08-2011 06:29 PM
hellosailor With that much space I'm surprised the client wanted a berth instead of a billiard table. Gyroscopically stabilized, of course.

I can only imagine the luxury of staying on one tack for an entire long watch. I still rather have a "head end" and a "foot end" to a berth, so even staying on one tack for the whole sleep, sooner or later that would have to be swapped.

Whatever happened to sailors sleeping in nice cozy hammocks?!
12-08-2011 06:14 PM
RXBOT I think wikipedia gives a different sanscrit translation than abode. As some say after a man emerges he spends most of the rest of his life trying to re-enter.Robert did you and your cronies at CA ever design something like ultimate sailing vessel for single handed cruise and circumnavigation?
12-08-2011 06:02 PM
bobperry Yes, that is what I said. That is what I drew. That is what the client wanted.

If you were going to short tack your way accross the Pacific it might be an issue. But this boat was not designed for short tacking duels.

I think the best aft berth I ever design was big enough so that you could sleep longitudinally or athwartships. That worked well.
12-08-2011 05:30 PM
hellosailor bob-
You say " The aft double berth was designed to be athwartships as Daryl, and a lot of other sailors I know, think this is the ultimate sea berth. "
Doesn't that leave you sleeping with your feet raised up above your head on one tack? I haven't had the chance to try it but don't see why sleeping athwartship at sea would be a good idea. Head athwarthship, sure. But bed??
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